PL Marine Fast Cure 10 Oz. This tough, paintable sealant dries white withstands both salt water and fresh water and does not shrink or bubble on damp surfaces. Loctite PL Marine Fast Cure Adhesive Sealant sets in just 30 minutes and fully cures in 24 hours for a watertight, flexible seal that’s ideal for through-hull fastening and deck fittings deck to hull joints, port lights, moldings, struts and planking and stem joints.